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<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      * {
        padding: 0;
        margin: 0;
      }
      /* .box {
        overflow: hidden;
      }
      .left {
        float: left;
        width: 200px;
        background: green;
        height: 400px;
      }
      .right {
        margin-left: 210px;
        background: #ccc;
        height: 200px;
      } */
      .box {
        display: flex;
        /* font-size: 12px; */
        /* align-items: flex-start; */
      }
      .left {
        width: 1rem;
        background: green;
        font-size: 0.1rem;
        /* font-size: 2em; */
      }
      .right {
        flex: 1;
        margin-left: 10px;
        background: #ccc;
      }
    </style>
  </head>
  <body>
    <div class="box">
      <div class="left">left</div>
      <div class="right">
        right
        <br />right<br />right<br />right<br />right<br />right<br />right<br />right
      </div>
    </div>
  </body>
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    //手机端的适配
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      document.getElementsByTagName('html')[0].style.fontSize =
        (document.documentElement.clientWidth / 750) * 100 + 'px'
    })

    window.onresize = function () {
      document.getElementsByTagName('html')[0].style.fontSize =
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